A polarizing plate is composed of a multilayered plastic optical film and provided on front and rear sides of a liquid crystal panel, and among these optical films, a polyvinyl alcohol (PVA) polarizing film on which a polarizing medium such as iodine, a dye, and the like is adsorbed, which is the essential part of the polarizing plate. The PVA polarizing film exhibits excellent polarizing properties, but has weak durability to temperature, humidity, and light, and thus protective films for protecting the PVA polarizing film need to be adhered to both sides of the PVA so as to complement the strength and durability.
Recently, polarizing plate protective films have a tendency to be developed as a high functional type having several simultaneous functions, and have been developed as an integrated type polarizing plate protective film having simultaneous functions such as hard coat treatment, anti-glare coating, anti-reflection coating, and the like, thereby realizing formation of a thin plate and price competitiveness. In particular, the use of the image liquid crystal device has been recently broadened the device in various fields, and thus interests in improving hardness of the polarizing plate and formation of the thin plate have been increasing.